-LRB- WIRED -RRB- -- Research In Motion is preparing to release its much-awaited response to the iPad , the BlackBerry PlayBook tablet , a month behind schedule .

Among other reasons , Adobe Flash is probably contributing to the delay .

The PlayBook was supposed to be out the first quarter of 2011 but is now set to release April 19 .

Some publications speculated on Thursday that the PlayBook 's late launch is related to touchscreen supply . The PlayBook also lacks a finished software development kit for making apps , and wo n't have native mail , messaging and contacts apps .

Difficulty getting Flash to work properly on the PlayBook is probably another one of RIM 's woes .

Let 's take a look at the evidence . First , other tablet makers have had trouble with Flash . Motorola 's Xoom launched without it , despite the fact that Motorola highlighted Flash support as a key feature .

Even though Flash Player 10.2 for Android is now available in the Android Market , the version meant for Android 3.0 Honeycomb -LRB- which the Xoom runs -RRB- is a prerelease version with significant limitations and lots of instability .

Second , sluggish performance and battery drainage have been problems for Flash before , and they 're the reason Apple CEO Steve Jobs gave for nixing Flash support on Apple 's mobile products .

The Samsung Galaxy Tab , which runs an earlier version of Android , is the only major tablet that currently supports a shipping version of the Adobe plugin .

Finally , Wired.com 's Erik Malinowski tried a PlayBook tablet at CES and reported that Flash performance proved to be a `` choppy and -LRB- ironically -RRB- limiting experience . ''

RIM officials at the time were tight-lipped about the tablet 's expected battery life , saying only that it would be more than an hour . That was an early version of the tablet , but choppiness in one of its key features does n't bode well .

Without great Flash support , a PlayBook tablet would practically have nothing to do .

Last year RIM drummed up Flash support for the upcoming PlayBook , saying that it was going to deliver the full internet experience . That would , in theory , give the PlayBook an edge over the iPad .

`` We 're not trying to dumb down the internet for a small mobile device , '' says Mike Lazaridis , RIM 's CEO , during the PlayBook demonstration . `` What we 're trying to do is bring up the performance and capability of the mobile device to the internet . ''

RIM 's planned April 19 launch lines up with Adobe 's claims that Flash will be available for tablets `` within a few weeks of Android 3 Honeycomb devices becoming available . ''

It 's been six weeks since Motorola released the Xoom , and April 19 is probably as long as Adobe can wait before Flash can no longer be considered `` a few weeks '' late .

Adobe and RIM did n't respond to a request for comment on this story .

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Copyright 2010 Wired.com .

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PlayBook supposed to be out the first quarter of 2011 , now releasing April 19

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Adobe Flash is probably contributing to the delay

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The PlayBook 's late launch is related to touchscreen supply , some speculate